The reason why this anime “Magical Meow meow Taruto” is very similar to this other old anime “Princess tutu.” Is because:

-Both main protagonists have the same aliases as “Princess.” When both of them aren’t actual princesses in a magical kingdom or castle. That they live in. They are not royalty. That’s just what they’re called/aslias or named most of the time.

-Both main protagonist characters are half animal/half human hybrid. When Taruto is a half human half cat, while Princess Tutu/Duck is half human half duck (with a secret identity).

-Both protagonist are female role/leads, who clearly look like children.

-Both main protagonists are heroines.

-There’s a male in “MMMT” named Nachos who’s tall and has a crush on the protagonist, it’s similar to how it was in “Princess Tutu” When Fakir developed a crush on Princess Tutu/Duck. Later in that series.

-Both main protagonists wear dresses.

-both animes have boring main characters (Iori & the other is Mytho).

-both characters often say their animal sounds frequently throughout the series. Such as Taruto says “meow” while Duck says “Quack.” As their habit of sounding like their animal species.

-Both shows had featured ghosts in them.

-Both of the female protagonists’ close friend groups are 2 female friends with them most of the time.

-both animes were released in the 2000s (this one 2001 while “Princess Tutu” is 2002).

-Both Duck/Princess Tutu and Taruto have a very similar personalities: they both Niave, both are a klutz, young, cute, heroic, (oh my goodness they both almost sound the same too).

-Both animes have similar genres: magical girl/supernatural, romance, fantasy, mystery, a little nit of horror, comedy.

-both animes are underrated, no longer ongoing & their mangas ended in the same years (2003).

-Both intro & outros are boring to listen to. To the point repetitive (which I’d often skipped).

-Both shows feature villians which some of them are elderly/seniors.

-both Taruto and Duck have the same hair styles (braids), both are small/short character in stature/height, both are heroines, as the main protagonists, & they both aren't so smart too.

I can see these 2 animes have tons of similarities.